This chapter addresses the question: what good are thinking-facts for us, in particular what good are such reflection arguments if we do not know the thinking premises of these arguments? It argues that far from running into a clash with sound epistemology, Descartes' metaphysics of thinking provides us with light at the other end of the tunnel — an epistemology that is a by-product of his naturalistic metaphysics of thinking. In a nutshell, for Descartes, there is no other a prioristic discipline of “normative Cartesian epistemology”. There is simply, all the way down, a metaphysics of cognitive relations. Some cognitions, provided they are properly generated in nature, are thinkings thereof; some cognitions, provided they are properly generated in nature, are knowings thereof; finally, some cognitions, provided they are not only generated by nature but are made by it of our nature, are fundamental-structural kinds of knowings.
Keywords: Descartes, thinking, knowing, cognition